Der Einflu� des Sauerstoffpartialdrucks und der Lichtintensit�t auf den ATP-Spiegel in Zellen von Athiorhodaceae

✍ Scribed by Sch�n, G. ;Bachofen, R.

• Publisher: Springer-Verlag
• Year: 1970
• Weight: 805 KB
• Volume: 73
• Category: Article
• ISSN: 0003-9276
• DOI: 10.1007/bf00409949

✦ Synopsis

1. When in dark cultures of Rhodo29seudomonas capsulata the pO~ was lowered from 110 to ~ 10 mm ]fig, the ATP level in the cells fell in average by 5 to 10~ . If the oxygen pressure was reduced further, approaching zero, the ATP content of the cells went down even more.

2. When semi-aerobic cultures (20 mm Hg) of t~hodopseudomonas ca~sulata were switched from darkness to bright light, ~owth changed little but the rate of baeteriochlorophyll synthesis was clearly reduced. Under corresponding experimental conditions strong illumination resulted in an increase of the ATP level in the cells after a lag period of several minutes.

3. In anaerobic light cultures of RhodospiriUum rubrum the ATP content of the cells dropped when the illumination was shifted from bright to dim light. 4. When anaerobic light cultures of l~hodospirillum rubrum were changed from dim to bright light, the ATP level in the cells increased only slowly, but dropped immediately, when the cultures were changed back to dim light.

4. The influence of the adenylate system on growth and the rate of bacteriochlorophyll synthesis is discussed.

Zusammen]assung.

1. In Dunkelkulturen fielder ATP-Spiegel yon Rhodopseudomonas eapsulata beim Absenken des 2~0~ yon 110 auf N 10 mm Hg im Durchsehnitt um 5--10~ ab. Eine weiterc Verringerung des GelSstsauerstoffs im Medium (gegen Null) liel] den ATP-Gehalt der Zellen weiter sinken. 2. Nach Beginn einer starken Belichtung ~nderten semiaerobe Kulturen yon l~hodopseudomonas ea2zsulata [20 mm I-Ig (pO2)] das Wachstum kaum, die B.-Chlorophyllsynthese wurde dagegen deutlich verringert. Unter entsprechenden experimentellen Bcdingnngen wurde durch alas Licht dcr ATP-Spiegel nach einer Lag-Periode yon mehreren Minuten erhSht. 3. Anaerobe Lichtkulturen yon .Rhodospirillum rubrum, die im Starklicht vorbebriitet wurden, erniedrigten bei anschlieBcnder Bestrahlung mit Sehwachlicht den ATP-Spiegel in den Zellen.